I have an 02 with 22k on the clock.

When i am driving everything is fine, but occasionally when i stop at a redlight it will miss a little, later it has been missing more and more. Not at every light though. Just when it kinda seems to want to.

I have checked all my hoses, and everything is fine.

I just swapped my tr6's for another set of new tr6's. Same thing before and after the plug swap. (br7's will be delivered mon.)

My engine mods are a 4lb and cold air. Truck is tuned, but always had this miss with every tuner.

anyone have any idea?

 

No SES light I take it?

If you know someone with a autotap (w/a laptop), you can see live what cylinder is misfiring.


One other thing... Does it do this *anytime* or only after the motor is warmed up? If it's fine when cold then mising after warm up? I'd suspect a coil pack maybe?

Rich

 

Check your coil packs. Also when was the last time you changed the fuel filter?

 

all fluids were changed 2k miles ago.

any other ideas? IAC ect?

 

The IAC will generally cause your RPM’s to fluctuate while sitting idle so I would rule that out if you’re actually getting a miss. I don’t think a fuel filter would cause it to miss either, if it did at idle then you would tend to see it worse while driving. Either is possible but I would be looking at the coil packs before the other things.

 

Copper plugs like to miss at idle.

Mine does it here and there.

Nothing to worry about in my eyes as long as eveything else checks out ok.

 

Yep NGK's SUCK on idle, Put Denso's in and your problems will go away.

I hated my TR-6's from the second I first started my truck up with them. Changed them after 500 miles and used Denso's for the next 2-1/2 years (PERFECT IDLE)

I got NGK BR7's now, and they SUCK on idle too

 

Not all NGK's suck Rob... THese Iridiums are as good/better that the Denso's and are not as $$$...
NGK IX iridium
Stock Number: 3690
Part Number: TR7IX
Unit Price: $7.60

or the TR8IX's

 

TR8IX's here.

 

NGK IX iridium
Stock Number: 3691
Part Number: TR8IX
Unit Price: $7.60

 

samiam513

Hey man how are you... Hope you get it fixed soon.. Gonna run in to you one day...........

PEacE........................
Jim

 

i checked the codes tonoght with the predator, and the #1 o2 is reading lean it says. It had three codes for that.

 

Hey, I had to respond to this because my truck has the EXACT same symptoms as yours. If it is the same thing, I don't believe it's a miss. I've had it on the predator and a brand new Snap-on scanner, and no misses are ever detected. The scanner also does a self test to find any plug not firing correctly, and came up with nothing.

I also get lean codes, and no voltage readings from my rear 02's while the truck is idling rough. I'd just call it idling rough for lack of more information. I have a wideband, and as soon as it starts acting up, it leans right out (pegs the gauge), and then returns to normal when the truck seems to straighten itself out.

I still don't know what it is yet. I haven't had time to bring it to the garage I go to, but I will tell you that while I had it there, we checked all of the usual stuff you hear on the boards here (IAC, vac leaks, MAF, etc).

Please let me know if you figure anything out, and of course I'll post if I find anything.

Good luck!

Aaron

edit: I just reread your post. I also checked different tuners programs, and also back to stock with no change... I don't think it's tune related. And, I run Denzo's.... so I don't think it's your copper plugs.

 

must just be silver 01-02l's then.

i am running fuel injector cleaner through it right now, 41% of a tank left. hasn't cleared up.

i unplugged each injector and coil one at a time, and everytime i unplugged one, it got worse so they are all fine.

No vac leaks.

my tune was pushing 30-40 deg spark advance in idle. 2 of my buddies who build motors found that to be a bit odd. Tonight i tried to restore my factory tune. Try 1 resulted in the predator saying it failed, try 2 got it. When i held it at 1500 rpm (where it misses the worse) it only missed a couple times. Nothing near what it was. I checked the spark advance and it was floating near 10-15.

so... i dunno. I am emailing my tuner tomm.

any more ideas?

 

Keep in mind that even a mild miss is going to look like a lean mixture to an oxygen sensor. When the motor misses it dumps raw fuel and LOTS of excess oxygen into the exhaust.

I doubt this is a fuel problem, more likely ignition. I'd start with the coils...